System and method for reducing heat transfer from a warm side to a cold side along an edge of an insulated glazing unit

ABSTRACT

A spacer bar for use in glazing units employs two heat blockage portions. One heat blockage portion is implemented as a low thermal conductivity planar plastic s wall portion, wherein the other heat blockage portion is of an extended length and is implemented as a low thermal conductivity non-planar plastic lined metal wall portion. The non-planar plastic lined metal wall portion, preferably including irregularities, such as ridges, ribs, or the like.

CROSS-REFERENCE TO RELATED APPLICATION

This Application claims the benefit of priority of U.S. Provisional Patent Application Ser. No. 60/840,841, filed Aug. 29, 2006.

BACKGROUND

The subject application is directed to a spacer bar for reducing heat transfer between panes of glazing in an insulated glazing unit. In particular, the subject application is directed to a spacer bar for reducing the amount of heat transferred from the warm side to the cold side along an edge of an insulated glazing unit.

Conventional insulating glazing units typically use a tubular spacer bar to separate panes of glazing forming the insulating glazing unit. The space between panes of insulating glass is typically filled with air or a colorless and odorless gas, such as argon. The addition of argon greatly increases the thermal performance of a window by minimizing heat transfer. The interior of the spacer bar is generally provided with a seal liner, which is composed of a thermoplastic material with good adhesion to the spacer frame and a low moisture vapor transmission. The seal liner serves to prevent moisture vapor penetration through the spacer frame, and to minimize the transfer of heat from the warm side to the cold side of an insulated glazing unit via the spacer bar. In addition, a secondary sealant is known to be used that envelopes the spacer bar for further reducing the heat transfer via the spacer bar. Yet, a heat flow across the spacer bar still exists.

SUMMARY OF INVENTION

In accordance with the subject application, there is provided an energy conservation device for implementation in an insulated glazing unit.

Further, in accordance with the subject application, there is provided a spacer bar for reducing the amount of heat transferred from the warm side to the cold side along an edge of an insulated glazing unit having an increased path length and minimal secondary sealant.

Still further, in accordance with one embodiment of the subject application, there is provided a spacer bar for an associated insulating glazing unit. The associated insulating glazing unit includes opposed first and second glazed structures. The spacer bar comprises a hollow elongated body including an internal chamber, a first heat blockage portion adapted for engaging with a corresponding edge of the first glazed structure, and a second heat blockage portion adapted for engaging with a corresponding edge of the second glazed structure. The first heat blockage portion and the second heat blockage portion are adapted to envelope the internal chamber. The first heat blockage portion is a generally planar wall portion of the hollow elongated body. At least one part of the second heat blockage portion is a generally non-planar wall portion of the hollow elongated body.

In one embodiment of the subject application, the at least one generally non-planar wall portion of the hollow elongated body comprises at least one irregularity. Dimensions of the at least one irregularity are determined by given thermal performance of the spacer bar.

In another embodiment of the subject application, the first heat blockage portion of the hollow elongated body comprises a low thermal conductivity plastic portion.

In another embodiment of the subject application, the second heat blockage portion of the hollow elongated body comprises a low thermal conductivity plastic lined metal portion.

Still other objects, advantages and aspects of the subject application will become readily apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of the subject application, simply by way of illustration of the best modes suited to carry out the subject application. As it will be realized by those skilled in the art, the subject application is capable of other different embodiments and its several details are capable of modifications in various obvious aspects all without departing from the scope of the subject application. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of the specification, illustrate several aspects of the subject application, and together with the description serve to explain the principles of the subject application. In the drawings:

FIG. 1 is a cross-sectional view of a spacer bar in accordance with one embodiment of the subject application;

FIG. 2 is a cross-sectional view of a spacer bar in accordance with one embodiment of the subject application;

FIG. 3 a is a cross-sectional view of a spacer bar in accordance with one embodiment of the subject application;

FIG. 3 b is a top view of a spacer bar in accordance with one embodiment of the subject application;

FIG. 3 c is a cross-sectional view of a metal member of a plastic lined metal member of a spacer bar in accordance with one embodiment of the subject application; and

FIG. 3 d is a cut-out view of a spacer bar in accordance with one embodiment of the subject application.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The subject application is directed to an energy conservation device for implementation in an insulated glazing unit. In particular, the subject application is directed to a spacer bar for reducing the amount of heat transferred from the warm side to the cold side along an edge of an insulated glazing unit.

Turning now to FIG. 1, there is shown a cross-sectional view of a spacer bar 100 for an associated insulating glazing unit (not shown in the drawing), in accordance with one embodiment of the subject application. As known in the art, the associated insulating glazing unit includes opposed first and second glazed structures (not shown). The spacer bar 100 includes a hollow elongated body including a first heat blockage portion adapted for engaging with a corresponding edge of the first glazed structure, and a second heat blockage portion adapted for engaging with a corresponding edge of the second glazed structure. As shown in FIG. 1, the first heat blockage portion is a generally planar wall portion 102 of the hollow elongated body. A part of the second heat blockage portion is a generally non-planar wall portion 104 of the hollow elongated body. The generally non-planar wall portion 104 of the hollow elongated body includes one or more irregularities illustrated in FIG. 1 as ridges 106. The skilled artisan will appreciate that the profile of the non-planar wall portion 104 including three ridges 106 is presented for illustration purposes only.

Those skilled in the art will recognize that the profile of the non-planar wall portion 104 is capable of being deformed in any suitable way, for example and without limitation, it can be bent, oblique, or corrugated. In the later case it can be wavy, or include, for example and without limitation, at least one rib, groove, or ridge. The dimensions of the irregularities of the profile of non-planar wall portion 104 of the spacer bar 100 are determined by given thermal performance of the associated insulated glazing unit, and specifically of the spacer bar 100. A skilled artisan will appreciate that the dimensions of the ridges 106 presented in FIG. 1 are for illustration purposes only and the instant subject application is not limited to those dimensions shown in FIG. 1. The first heat blockage portion of the hollow elongated body, implemented as the generally planar wall portion 102, is a low thermal conductivity plastic member. The second heat blockage portion of the hollow elongated body is advantageously a low thermal conductivity plastic lined metal member.

The plastic lined metal member of the second heat blockage portion includes a metal member 108 and a plastic liner member 110 fixedly attached to the metal member 108. As will be recognized by those skilled in the art, the plastic liner member 110 is capable of being fixedly attached to the metal member 108 via any suitable means, such as bonding, adhesive means, and the like. A skilled artisan will further appreciate that the metal member 108 is capable of implementation of stainless steel, other suitable metal, or suitable multilayer tape. The metal member 108 is also capable of being butyl-wrapped. As shown in FIG. 1, a thickness of the plastic liner member 110 exceeds a thickness of the metal member 108. A skilled artisan will appreciate that the dimensions presented in FIG. 1 are for illustration purposes only and the instant subject application is not limited to the angular, thickness, width, lengths, and materials shown in FIG. 1.

The plastic liner member 110 is advantageously made of an elastically-plastically deformable material. As known in the art, preferred materials of the type include synthetic or natural materials that undergo plastic, irreversible deformation after the elastic restoring forces of the bent material have been overcome. In such preferred materials, substantially no elastic restoring forces are active after deformation (bending) of the metal member 108 beyond its apparent yielding point. Representative plastic materials also preferably exhibit a relatively low heat conductivity (i.e., preferred materials are heat-insulating materials), such as heat conductivities of less than about 5 W/(mK), more preferably less than about 1 W/(mK), and even more preferably less than about 0.3 W/(mK). Particularly preferred materials for the plastic liner member 110 are thermoplastic synthetic materials including, but not limited to, polypropylene, polyethylene terephthalate, polyamide and/or polycarbonate. The plastic material(s) may also contain commonly used fillers (e.g. fibrous materials), additives, dyes, UV-protection agents, etc. The material of the plastic member of the generally planar wall portion 102 is capable of being analogous to that of the material of the plastic liner member 110, as will be understood by those skilled in the art.

The metal member 108 includes a first edge 112 and a second edge 114. As shown in FIG. 1, the first and second edges 112, 114 of the metal member 108 engage with respective edges of the generally planar wall portion 102 of the first heat blockage portion. In the embodiment of FIG. 1, the first and second edges 112, 114 of the metal member 108 each include a folded portion 116, 118, respectively. The folded portions 116, 118 protrude in a direction generally orthogonal to the generally planar wall portion 102. As will be appreciated by those skilled in the art, the folded portions 116, 118 form respective legs that allow for adjustments with respect to specific dimensions of an associated insulated glazing unit.

As illustrated in FIG. 1, the cross-sectional view of the spacer bar 100 indicates internal chamber 120, such as a hollow opening, running lengthwise of the spacer bar 100. The internal chamber 120 is enveloped by the first heat blockage portion and the second heat blockage portion. The contents of the internal chamber 120 may include any suitable material known in the art of glazing unit manufacturing, such as a thermally-insulative gas, a thermally-insulative material, and a desiccant material. In other embodiments of the subject application, the internal chamber 120 contains a low-heat transfer material, such as a foam, or the like, advantageously having low-conductivity with respect to heat transfer. As will be understood by those skilled in the art, one or more linear-key members or corner key members (not indicated in FIG. 1) are advantageously used so as to provide a continuous piece of spacer material, as known in the art. Those skilled in the art will appreciate that the subject application is not limited to a single continuous piece and that a number greater than one of spacer pieces are equally capable of being used in accordance with the subject application. The overall height of the spacer, illustrated in FIG. 1, is 0.330″, which provides increased stiffness to the spacer bar 100 over conventional spacer bars, as will be appreciated by those skilled in the art. In an alternate embodiment, the height of the spacer is 0.276″.

Referring now to FIG. 2, there is shown a cross-sectional view of a spacer bar 200 for an associated insulating glazing unit (not shown in the drawing), in accordance with another embodiment of the subject application. The spacer 200 illustrated in FIG. 2, the same as in the embodiment of FIG. 1, includes a hollow elongated body including a first heat blockage portion adapted for engaging with a corresponding edge of the first glazed structure, and a second heat blockage portion adapted for engaging with a corresponding edge of the second glazed structure of an associated insulating glazing unit. As shown in FIG. 2, the first heat blockage portion is a generally planar wall portion 202 of the hollow elongated body. A part of the second heat blockage portion is a generally non-planar wall portion 204 of the hollow elongated body. The generally non-planar wall portion 204 of the hollow elongated body includes one or more irregularities illustrated in FIG. 2 as ridges 206. The skilled artisan will appreciate that the profile of the non-planar wall portion 204 including three ridges 206 is presented for illustration purposes only.

As mentioned above with respect to the non-planar wall portion 104 of the embodiment of FIG. 1, the profile of the non-planar wall portion 204 is capable of being deformed in any suitable way, for example and without limitation, it can be bent, oblique, or corrugated. In the later case it can be wavy, or include, for example and without limitation, at least one rib, groove, or ridge. The dimensions of the irregularities of the profile of non-planar wall portion 204 of the spacer bar 200 are determined by given thermal performance of the associated insulated glazing unit, and specifically of the spacer bar 200. A skilled artisan will appreciate that the dimensions of the ridges 206 presented in FIG. 2 are for illustration purposes only and the instant subject application is not limited to those dimensions shown in FIG. 2. The first heat blockage portion of the hollow elongated body, implemented as the generally planar wall portion 202, is a low thermal conductivity plastic member. The second heat blockage portion of the hollow elongated body is advantageously a low thermal conductivity plastic lined metal member.

The plastic lined metal member of the second heat blockage portion includes a metal member 208 and a plastic liner member 210 fixedly attached to the metal member 208. As will be recognized by those skilled in the art, the plastic liner member 210 is capable of being fixedly attached to the metal member 208 via any suitable means, such as bonding, adhesive means, and the like. A skilled artisan will further appreciate that the metal member 208 is capable of implementation of stainless steel, other suitable metal, or suitable multilayer tape. The metal member 208 is also capable of being butyl-wrapped (not shown in the drawing). As shown in FIG. 2, a thickness of the plastic liner member 210 exceeds a thickness of the metal member 208. A skilled artisan will appreciate that the dimensions presented in FIG. 2 are for illustration purposes only and the instant subject application is not limited to the angular, thickness, width, lengths, and materials shown in FIG. 2.

The plastic liner member 210 is capable of being made of a material analogous to that of the plastic liner member 110, described in detail above with respect to FIG. 1, as will be understood by a skilled artisan. The metal member 208 includes a first edge 212 and a second edge 214. As shown in FIG. 2, the first and second edges 212, 214 of the metal member 208 engage with respective edges of the generally planar wall portion 202 of the first heat blockage portion. As illustrated in FIG. 2, the cross-sectional view of the spacer bar 200 indicates internal chamber 216, such as a hollow opening, running lengthwise of the spacer bar 200. The internal chamber 216 is enveloped by the first heat blockage portion and the second heat blockage portion. The contents of the internal chamber 216 may include any suitable material known in the art of glazing unit manufacturing, such as a thermally-insulative gas, a thermally-insulative material, and a desiccant material. In other embodiments of the subject application, the hollow contains a low-heat transfer material, such as a foam, or the like, advantageously having low-conductivity with respect to heat transfer. As will be understood by those skilled in the art, one or more linear-key members or corner key members (not indicated in FIG. 2) are advantageously used so as to provide a continuous piece of spacer material, as known in the art. Those skilled in the art will appreciate that the subject application is not limited to a single continuous piece and that a number greater than one of spacer pieces are equally capable of being used in accordance with the subject application. The overall height of the spacer, illustrated in FIG. 1, is 0.330″, which provides increased stiffness to the spacer bar 200 over conventional spacer bars, as will be appreciated by those skilled in the art. In an alternate embodiment, the height of the spacer is 0.276″. The skilled artisan will further appreciate that in the spacer 200 illustrated in FIG. 2, unlike the spacer bar 100 illustrated in FIG. 1, the edges 212, 214 of the metal member 208 do not include a folded portion that protrudes in a direction orthogonal to the planar wall portion 202. Instead, the spacer bar 200 incorporates an additional amount of materials such that no folded portion is needed to extend the height of the spacer 200 to 0.330″, as set forth in FIG. 1.

Turning now to FIG. 3 a, there is shown a cross-sectional view of a spacer bar 300 for an associated insulating glazing unit (not shown in the drawing), in accordance with another embodiment of the subject application. The spacer bar 300 illustrated in FIG. 3 a, the same as in the embodiments of FIG. 1, and FIG. 2 includes a hollow elongated body including a first heat blockage portion adapted for engaging with a corresponding edge of the first glazed structure, and a second heat blockage portion adapted for engaging with a corresponding edge of the second glazed structure of an associated insulating glazing unit. As shown in FIG. 3 a, the first heat blockage portion is a generally planar wall portion 302 of the hollow elongated body. A part of the second heat blockage portion is a generally non-planar wall portion 304 of the hollow elongated body. The generally non-planar wall portion 304 of the hollow elongated body includes one or more irregularities illustrated in FIG. 3 a as ridges 306. The skilled artisan will appreciate that the profile of the non-planar wall portion 304 including three ridges 306 is presented for illustration purposes only.

As mentioned above with respect to the non-planar wall portions 104, 204 of the embodiments of FIG. 1 and FIG. 2, respectively, the profile of the non-planar wall portion 304 is capable of being deformed in any suitable way, for example and without limitation, it can be bent, oblique, or corrugated. In the later case it can be wavy, or include, for example and without limitation, at least one rib, groove, or ridge. The dimensions of the irregularities of the profile of non-planar wall portion 304 of the spacer bar 300 are determined by given thermal performance of the associated insulated glazing unit, and specifically of the spacer bar 300. The embodiment shown in FIG. 3 a differs from the above described embodiments of FIGS. 1, 2 by the configuration and dimensions of irregularities of the profile of non-planar wall portion 304. A skilled artisan will appreciate that the dimensions of the ridges 306 presented in FIG. 3 a are for illustration purposes only and the instant subject application is not limited to those dimensions shown in FIG. 3 a. The first heat blockage portion of the hollow elongated body, implemented as the generally planar wall portion 302, is a low thermal conductivity plastic member. The second heat blockage portion of the hollow elongated body is advantageously a low thermal conductivity plastic lined metal member.

The plastic lined metal member of the second heat blockage portion includes a metal member 308 and a plastic liner member 310 fixedly attached to the metal member 308. As will be recognized by those skilled in the art, the plastic liner member 310 is capable of being fixedly attached to the metal member 308 via any suitable means, such as bonding, adhesive means, and the like. A skilled artisan will further appreciate that the metal member 308 is capable of implementation of stainless steel, other suitable metal, or suitable multilayer tape. The metal member 308 is also capable of being butyl-wrapped. As shown in FIG. 3 a, a thickness of the plastic liner member 310 exceeds a thickness of the metal member 308. A skilled artisan will appreciate that the dimensions presented in FIG. 3 a are for illustration purposes only and the instant subject application is not limited to the angular, thickness, width, lengths, and materials shown in FIG. 3 a.

The plastic liner member 310 is capable of being made of a material analogous to that of the plastic liner members 110, 210 described in detail above with respect to FIGS. 1, 2, as will be understood by a skilled artisan. The metal member 308 includes a first edge 312 and a second edge 314. As shown in FIG. 3 a, the first and second edges 312, 314 of the metal member 308 engage with respective edges of the generally planar wall portion 302 of the first heat blockage portion. As illustrated in FIG. 3 a, the cross-sectional view of the spacer bar 300 indicates internal chamber 316, such as a hollow opening, running lengthwise of the spacer bar 300. The internal chamber 316 is enveloped by the first heat blockage portion and the second heat blockage portion. The contents of the internal chamber 316 may include any suitable material known in the art of glazing unit manufacturing, such as a thermally-insulative gas, a thermally-insulative material, and a desiccant material. In other embodiments of the subject application, the internal chamber 316 contains a low-heat transfer material, such as a foam, or the like, advantageously having low-conductivity with respect to heat transfer. As will be understood by those skilled in the art, one or more linear-key members or corner key members (not indicated in FIG. 3 a) are capable of being advantageously used so as to provide a continuous piece of spacer material, as known in the art. Those skilled in the art will appreciate that the subject application is not limited to a single continuous piece and that a number greater than one of spacer pieces are equally capable of being used in accordance with the subject application.

FIG. 3 b further illustrates a top view 318 of the spacer bar 300, FIG. 3 c shows a cross-sectional view 320 of the metal member 308 of a plastic lined metal member of the spacer bar 300, and FIG. 3 d shows a cut-out view 322 illustrating engaging of the second edge 314 of the metal member 308 with a respective edge of the planar wall portion 302 of the first heat blockage portion, in accordance with the subject application. In a preferred embodiment, the metal member 308 has a thickness of approximately 0.0039″.

As illustrated by the cross-sectional view of the metal member 308 in FIG. 3 c, the metal member 308 is pre-bent into an acceptable shape for coupling with the plastic liner member 310. The plastic liner member 310 is formed to create tubular hollow internal chamber 316, running lengthwise of the spacer bar 300, indicated in FIG. 3 a. The skilled artisan will further appreciate that similar to the spacer bar 200 of FIG. 2, in the spacer bar 300 illustrated in FIG. 3 a, the edges 312, 314 of the metal member 308 do not include a folded portion that protrudes in a direction orthogonal to the planar wall portion 302, as in the embodiment shown in FIG. 1. In contrast, the spacer bar 300 incorporates an additional amount of materials such that no folded portion is needed to extend the height of the spacer 300 to 0.330″, as set forth in FIG. 1. The skilled artisan will appreciate that the dimensions presented in FIG. 3 are for illustration purposes only and the subject application is not limited to the angular, thickness, width, lengths, and materials shown in FIG. 3.

The forgoing description allows for appreciation of significant advantages associated with disclosed structure. The disclosed spacer bar technology results in a higher stiffness. This advantage is attributable to the shape and dimensions chosen for the spacer design. A height of a space is suitably 0.33 inches, which is more than the 0.276 inches to which earlier bending machines have been adjusted. The disclosed spacer also allows for improved, lowered thermal conductivity. This is resultant from a longer metal path and missed sealing at a lower portion that forms a secondary seal. The improved design counteracts thermal loss that would otherwise be expected given a presence of such a secondary seal. The absence of this seal also results in a substantial cost savings during fabrication.

Those skilled in the art will further recognize that the heat transfer across the embodiments of the spacer bar of the subject application, illustrated in FIGS. 1, 2, and 3, is minimized by suitably employing two heat blockage portions, one of which is implemented as a planar plastic wall portion, wherein the other heat blockage portion is of an extended length and is implemented as a non-planar plastic lined metal wall portion, preferably including irregularities, such as ridges, ribs, or the like.

It will further be understood by those skilled in the art that the shape and construction of the spacer bar, as illustrated FIGS. 1, 2, and 3, enables vast cost-savings in the reduced amount of secondary sealant required by the subject application. The secondary sealant volume per foot of common spacers is typically 0.891 cubic inches per foot that results in 25.9 units per gallon of sealant for 2′×3′ units. With a sealant price of $19.20 per gallon, each 2′×3′ unit with a full secondary sealant includes $0.74 per unit for the secondary sealant. As the skilled artisan will appreciate with respect to the spacer bar illustrated in FIGS. 1-3, the estimated secondary sealant volume per unit is only 0.220 cubic inches per foot or only about ¼ the full coverage and a $0.19 per unit sealant cost. Thus, there is a savings of $0.55 per unit. Therefore, a high volume insulated glazing manufacturer will realize substantial annual savings.

The foregoing description of a preferred embodiment of the subject application has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the subject application to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described to provide the best illustration of the principles of the subject application and its practical application to thereby enable one of ordinary skill in the art to use the subject application in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the subject application as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. 

1. A spacer bar for an associated insulating glazing unit, which associated insulating glazing unit includes opposed first and second glazed structures, the spacer bar comprising: a hollow elongated body including: an internal chamber; a first heat blockage portion adapted for engaging with a corresponding edge of the first glazed structure; and a second heat blockage portion adapted for engaging with a corresponding edge of the second glazed structure; wherein the first heat blockage portion and the second heat blockage portion are adapted to envelope the internal chamber; wherein the first heat blockage portion is a generally planar wall portion of the hollow elongated body; and wherein at least one part of the second heat blockage portion is a generally non-planar wall portion of the hollow elongated body.
 2. A spacer bar for an associated insulating glazing unit of claim 1: wherein the at least one generally non-planar wall portion of the hollow elongated body comprises at least one irregularity; wherein dimensions of the at least one irregularity are determined by given thermal performance of the spacer bar.
 3. A spacer bar for an associated insulating glazing unit of claim 1 wherein the first heat blockage portion of the hollow elongated body comprises a low thermal conductivity plastic member.
 4. A spacer bar for an associated insulating glazing unit of claim 1 wherein the second heat blockage portion of the hollow elongated body comprises a low thermal conductivity plastic lined metal member.
 5. A spacer bar for an associated insulating glazing unit of claim 4 wherein the low thermal conductivity plastic lined metal member of the second heat blockage portion of the hollow elongated body comprises: a metal member including a first edge and a second edge; and a plastic liner member fixedly attached to the metal member; wherein a thickness of the plastic liner member exceeds a thickness of the metal member.
 6. A spacer bar for an associated insulating glazing unit of claim 5 wherein the first and second edges of the metal member are adapted for engaging with respective edges of the generally planar wall portion of the first heat blockage portion of the hollow elongated body.
 7. A spacer bar for an associated insulating glazing unit of claim 6 wherein the first and second edges of the metal member each include a folded portion adapted for protruding in a direction generally orthogonal to the generally planar wall portion of the hollow elongated body.
 8. A spacer bar for an associated insulating glazing unit of claim 1 wherein the first heat blockage portion of the hollow elongated body opposes the at least one generally non-planar part of the second heat blockage portion of the hollow elongated body.
 9. A spacer bar for an associated insulating glazing unit of claim wherein the internal chamber of the hollow elongated body is filled at least partially with a desiccant.
 10. A spacer bar for an associated insulating glazing unit of claim 1 wherein the internal chamber of the hollow elongated body is filled at least partially with a thermally-insulative material. 